With a decreasing intensity and frequency of freeze events, coastal wetlands globally are undergoing ecosystem transitions as the poleward expansion of mangroves encroaches into salt marsh, especially in tropical-temperate transitional zones. Such transition triggers changes in coastal wetland ecosystem services, including coastal protection, nutrient removal and wildlife habitat. Here, we characterized how mangroves respond to temperature minima across levels of community, population and individual at 18 sites along Florida’s Gulf of Mexico coast (USA), to provide implication for coastal ecological engineering projects such as living shoreline and coastal accretion to adapt sea level rise. Warming scenarios could trigger linear accumulation of mangrove biomass, and canopy height and coverage of mangroves in north could experience dramatic increase to resemble the landscape in south mangroves. Species-specifically, A parabolic and positive linear relationship with temperature minima were found for abundance and coverage of tall A. germinans and tall R. mangle population respectively, suggesting R. mangle might take over dominancy from the pioneering A. germinans with warming scenarios. The projections suggested a faster rate of elevation accretion, enhanced coastal protection, alteration of habitats for fishery and increasing need for site-specific mangrove management while implementing traditionally marsh-based living shoreline in Northwest Florida.